Uaru

Uaru amphiacanthoides

Cichlids - South American

A large, relatively peaceful but highly gregarious South American cichlid. Often kept with Discus due to their shared need for very warm, pristine, acidic water. They are notorious herbivores that will devour almost any aquatic plant, and they actually require grazing on driftwood for proper digestion. They must be kept in groups.

At a Glance

Adult Size25 cm
Body ShapeCompressed
Growth RateModerate
TemperamentMostly Peaceful
Water TypeFreshwater Only
Flow PreferenceLow
Waste OutputHigh
StockingGroup of 4+

Tank Requirements

Minimum Volume400 L
Minimum Length150 cm
FlowLow
Water TypeFreshwater Only
Must-Haves in the Tank
Driftwood (Digestion/Hiding)Sand (Sifters)

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Water Parameters

Temperature2730°C
pH57
Hardness18 dGH

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Keep water parameters stable with the right testing and heating gear.

Temperament & Compatibility

Aggression LevelMostly Peaceful
4/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least4 fish
Max per TankNo limit
Can Live Alone?No — needs a group
Behavior Traits
Plant DestroyerShy / Slow Moving (Easily Stressed)Shrimp Eater

Available Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard (Adult)

The adult form, distinguished by a silver/yellowish-brown body with a prominent, large dark wedge or teardrop shape on the flank. Very deep-bodied.

Differs in 1 trait from base species

Also known as: Adult Uaru, Triangle Cichlid

Behavior Traits
Plant DestroyerShy / Slow Moving (Easily Stressed)Shrimp Eater

Juvenile (Grow-out)

Juveniles look completely different from adults, featuring dark mottling and spots designed to camouflage them in leaf litter. They grow rapidly and will quickly require a massive tank upgrade to accommodate their adult size and social group.

Differs in 5 traits from base species

Also known as: Baby Uaru, Spotted Uaru

Adult Size6 cm
Min Volume200 L
Min Length100 cm
Growth RateFast
Behavior Traits
Plant DestroyerShy / Slow Moving (Easily Stressed)

Uaru Care Guide Summary

The Uaru, scientifically known as Uaru amphiacanthoides, belongs to the Cichlids - South American family group. Adults reach a maximum size of approximately 25 cm and have a compressed body shape with a moderate growth rate. Classified as mostly peaceful, this species primarily occupies the mid-level and bottom zones of the aquarium and produces a high level of biological waste.

To thrive, the Uaru requires a freshwater only aquarium with a minimum volume of 400 litres and a tank length of at least 150 cm. Water temperature should be maintained between 27°C and 30°C, with a pH range of 57 and a general hardness of 18 dGH. A low water flow is preferred. An aquarium test kit can help you monitor these values.

The Uaru is a rewarding species to keep, provided its core environmental needs are met. This species is available in 2 varieties: Standard (Adult) and Juvenile (Grow-out). Each may differ slightly in size, temperament, or care needs, so it is worth checking the specific requirements of the variety you plan to keep.

Uaru Habitat Setup

When setting up an aquarium for the Uaru, a low water flow best suits their natural preferences. Because this species occupies the mid-level and bottom zones, the aquarium layout should prioritise open swimming space in the centre of the tank for free movement and sufficient floor space with hiding spots among rocks, wood, or dense planting. Useful additions include a sand substrate to accommodate their sifting behaviour and driftwood, which can serve as both a hiding place and a dietary supplement. Keepers should note that live planted layouts may be difficult to maintain, as this species tends to uproot or consume vegetation. Browse aquarium sand substrate options to find the best fit.

Uaru Compatibility Notes

Classified as mostly peaceful, the Uaru is a social species that requires the company of its own kind to thrive. When choosing tankmates, ornamental shrimp are not safe companions and boisterous or fast-moving tankmates may cause this species undue stress. Selecting tankmates that favour different water layers from the mid-level and bottom zones can help reduce competition and territorial overlap.

Frequently Asked Questions About Uaru

How big does Uaru get?+
Uaru (Uaru amphiacanthoides) typically reaches a maximum adult size of approximately 25 cm. They have a compressed body shape and a moderate growth rate.
What tank size does Uaru need?+
A minimum aquarium volume of 400 litres and a tank length of at least 150 cm are recommended for Uaru. This ensures enough swimming space and helps maintain stable water conditions.
What water parameters does Uaru need?+
Uaru thrives in freshwater only conditions with a temperature range of 27–30°C, a pH between 5 and 7, and a general hardness of 1–8 dGH. A low water flow is preferred.
Is Uaru peaceful or aggressive?+
Uaru is classified as mostly peaceful with an aggression score of 4 out of 10. They are generally well-suited to peaceful community tanks.
Can Uaru live alone?+
No, Uaru should be kept in groups of at least 4 to reduce stress and encourage natural behaviour.
Is Uaru safe with shrimp?+
No. Uaru is known to eat ornamental shrimp and is not recommended for shrimp tanks. Even larger shrimp species like Amano Shrimp may be at risk.
Does Uaru have any special tank requirements?+
Yes. Uaru benefits from driftwood (digestion/hiding) and sand (sifters) in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

Similar Species

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Oscar

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Red Devil Cichlid

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